TRS-80 Microcomputer News - Volume 3 Issue 03 (1981-03)(Radio Shack)(US)

TRS-80:

March, 1981

Microcomputer NEWS

P.O. Box 2910, Fort Worth, Texas 76101 £

THE MICROCOMPUTER NEWSLETTER PUBLISHED FOR TRS-80 OWNERS

Fort Worth
Scene

Volume 3, Issue 3

M

Ins
^r Y ill

Mr. Dave McGIumphy of Red Bank r
TN. sent us a letter in Mid-December (and
you are reading about it in middle March
if everything remains on schedule, which
illustrates our time delays). The letter had
three basic parts, two of which seem to
reflect the views of many of our readers,
and one of which was a helpful piece of
information for Model I users. The infor-
mation for Model I users can be found on
page 4 of the newsletter with other Model
I/III information.

(Continued on page 2)

MORE COMPUTER
CLUBS

Central Alabama Microcomputer Society
c/o Lewis E. Garrison
6375 Pinebrook Drive
Montgomery, AL 36117

1/205-272-8462

Dal-Clf Computer Club— TRS-80
c/o R. E. Smith
3716 Shady Hollow Ln.
Dallas, Tx. 75233

1/214-331-2665

Napervilie Central High School
Computer Club
440 West Aurora Avenue
Napervilie, Illinois 60540

PROCOMP*
844 Vernon St.
Manchester, CT 06040

Texhoma Microcomputer Enthusiasts
Wichita Valley TRS-80 Users Group
P.O. Box 4391
Wichita Falls, Texas 76308

JOHNS HOPKINS LAUNCHES
NATIONAL SEARCH— PERSONAL

COMPUTING NEWSLErreRiNDEx

TOn 7Y% Tor iW A "A5 ISSUE . . .

/\l \ J ^ JflJD Double Precision Square Root 4

•vr w m ww*. <* ^% w v-**^*-*.**. Education Products Page 7

HANDIG\PPED FortWorthScene..." 1

IJXXL^-L/l^rit-rjii/ Johns Hopkins Launches 1

The first national search for ideas Model I/III

and inventions through which the full Bugs, Errors and Fixes 6

spectrum of personal computing technol- Graphics Routine 4

ogy can be harnessed to assist the handi- Machine Sort ..." 13

capped was announced recently by The Manual Error (Mod III Level I) . 16

Johns Hopkins University. PRINT® Problem 4

To be conducted by the Applied Printer Routine 18

Physics Laboratory of the University, and Model II

with the National Science Foundation and Bugs, Errors and Fixes 12

Radio Shack, a division of the Tandy Cor- Diskette Problem 20

poration, as cosponsors, the effort will be Machine Sort 19

highlighted by a national competition for More Computer Clubs ........ 1

ideas, devices, methods, and computer Notes on Previous Newsletters 2

programs to help handicapped people Pocket Computer

overcome difficulties in learnings, work- Measurement Conversion 17

ing, and successfully adapting to home Product Line Manager Pages

and community settings. Categories that Color Computer 9

may be addressed include* computer- Model I/III 5

based aids for the blind, deaf and men- Model II 10

tally retarded; for individuals with learning Peripherals 8

disabilities, neurological or neuromuscu- Pocket Computer ............. 11

lar conditions; and the orthopedically Stop that Out-of~Sorts Feeling ...... 13

handicapped. (Continued on page 2) View from the 7th Floor 3

Retail Prices in this newsletter may vary at individual stores and dealers. 1
The company cannot be liable for pictorial and typographical inaccuracies. *

Radio /haell— The biggest name in little computers*

<TM)

JohnS HopMnS (frompagel)

One hundred awards will be made,
including a $10,000 grand prize, personal
computer equipment, other cash prizes,
computer training, and certificates of
merit. Entries will be sought from com-
puter specialists, full-time high school and
college students, and from interested
people generally, including those with
handicaps. Regional and national awards
will be made in all categories. National
awards will be presented at a banquet in
the fall of 1981 in the Washington D.C.
area.

Paul L. Hazan, director of the Per-
sonal Computing to Aid the Handicapped
project, said the competition is a chal-
lenge to the American people to use their
conceptual skills in bringing forth practical
aids based on computer technology that
will help an individual or group of people
with a handicap. "Just as important will be
the opportunity provided the inventors
and developers to make contact and form
partnerships with the handicapped in a
way that can lead to wide acceptance and
use of the new computing technology,"
Hazan stressed.

Orientation meetings are being
scheduled at major rehabilitation centers
throughout the United States to bring
together potential "inventors," handi-
capped people and professionals in habi-
litation-rehabiiitation fields. Special pre-
sentations also will be made nationwide
at chapter meetings of the Association for
Computing Machinery (ACM), Institute of
Electrical and Electronics Engineers
(IEEE), and personal computer clubs.

Contestants will have from Novem-
ber 25, 1980 until June 30, 1981 to pre-
pare and submit their entries.

To obtain additional information
including a descriptive flyer and contest
application, write to Personal Computing
to Aid the Handicapped, Johns Hopkins
University, Post Office Box 670, Laurel,
Maryland 2081.0.

Ft. Worth

(from page 1)

The first part of his letter dealt with
the new subscription based newsletter.
Here are his comments:

"The November Newsletter (which I
received on December 2) says that you
want $12/year for the Newsletter. I am
somewhat grudgingly sending it, but I'm
afraid that you won't send $12 worth of
information compared to publications
such as 80-Microcomputing. I hope that
Fll be pleasantly surprised, After all, I'd feel
really dumb paying you $12 to read your
advertising. The Newsletter has a lot of
potential. I hope it pays off, and I hope I *
can contribute to its value ..."

Mr. McGlumphy's last paragraph
pointed out an apparent discrepancy
between our statement in the November
Newsletter that "... our Model I factory
... is running at full speed.", and other
sources, including our own customer ser-
vice people, at about the same time.
When the article was written, the state-
ment was true. Unfortunately, the long
time between when we write our mate-
rial, and when you actually read it, some-
times makes it appear that we are giving
you bad information. We can assure you
that it is our intention to always give you
the best information we have AT THE
TIME we write our material.

Hopefully, most of you who are
reading this issue of the Newsletter have
also seen the December- February issues.
Over these last four issues, we have
worked very hard to reduce the amount
of "hard" advertising to virtually nothing.
In the months before December, we had
the "Product News" which was eight
pages of hard advertising. As you know
from this and other recent issues, we
have eliminated this section. In its place
we have the Product Line Manager's
pages. We hope that you find these pages
informative and useful.

We are not and will never be 80-
Microcomputing or any of the other mag-
azines. What we are is a source of direct
and "reasonably" valid information which
is intended to help you, our customers. I
say "reasonably" because we do make
mistakes, and plans do change. A prime
example of this is the method of mailing
the Newsletter. We told you in November
that the Newsletter would be mailed first
class beginning in January. We believed
this and planned on it. As the January
issue went to press, with the needed
changes for first class mailing, we had to
change and continue mailing third class.
As a result, we will continue to mail free
newsletters by third class. Paid subscrip-
tions are being mailed first class. The
information we gave you in November
was the best available at that time.

For some of you who have been
long time owners of TRS-80s this may be
your last issue. If you have decided to not
subscribe, tell us why! Wrong informa-
tion? Not enough of a particular type of
information? Help us serve you and oth-
ers better by communicating with us.

We will say in advance, that there are
certain things which we know you want:
Advanced Product information, informa-
tion on non-Radio Shack products, etc.
These are topics which, in general, we
simply can not address.

We are trying to give you a informa-
tive and usable newsletter about Radio
Shack computers and computer'- related
merchandise. We do not accept outside
advertising, and as of January we do not
even carry our own ads. If you like what
we are doing tell us. If you don't like it, tell
us that too, and then go on to suggest
ways that we can change to give you
what you need. A simple "I don't like it."
really doesn't help at all.

Notes on Previous
Newsletters

Mr. Lewis E. Garrison of Mont-
gomery, Alabama sent us this note on
Budget Management:

"In the November issue of the "TRS~
80 Microcomputer News," you gave
instructions on how to edit the Budget
Management (26-1603) program for use
on an 80 column printer. These instruc-
tions were easy to follow and worked
fine. However the title and date now need
to be centered. Here are the additional
changes to the REPORTS program that
need to be made to center the title and
date of the reports:

"1. Edit line 3530. Change the "40"
after the TAB to "26." Change the "25" in
the STRINGS statement to 22."

"2. Edit line 3540. Change the "40"
after the first TAB to "26." Change the "45"
after the second TAB to "3 1 ."

"With these changes made, you will
now have a professional looking output
product from your 80 column printer ..."

We would like to thank Mr. Garrison
for pointing out this oversight on our part,
and for providing the needed changes to
make your printouts more attractive.

View From the 7th Floor

by Jon Shirley, Vice President Computer Division

I have received a lot of letters about
our dropping the Model I and about the
FCC, so let's revisit that issue one last
time. The FCC regulations require that
"home computers" (and they defined the
term), manufactured after 1/1/1981 meet
certain new standards for interference
with TV sets, radios etc. (You Model II
owners can skip this part as the Model II
is not covered by these regulations but by
another set that also covers big and huge
computers and does not take effect for a
while.) The key word is manufactured —
computers made before January 1 can be
sold and, with the normal inventory situ-
ation, I doubt that very many FCC certified
computers have been actually purchased
by now.

The Color Computer had to have
specific certification, to a different stan-
dard, because it attaches to a Color TV,
before we could sell any so it has always
been certified. When we finally got the
new regulations, and it took a long time to
get them and then figure out what they
really meant, we started to see what
would have to be done to each product to
meet the requirements. To make a long
story short we discovered that it took
many, many engineering man hours, out-
side consultants, special very expensive
test equipment, an outside test site that is
usually in the middle of a farm and many,
many design changes to the computer. It
took new circuit board layouts, metal
shields, added capacitors, shielded rib-
bon cable (very expensive) plus a little
black magic to meet the requirements.
Shortly after I wrote my November col-
umn it became obvious that there was no
way to make the Model I meet the
requirements without a total redesign.
Since the Model III was, in effect, a totally
redesigned Model I, our decision became
obvious also.

In December we received FCC certi-
fication for all versions of the Model III and
started producing the FCC certified ver-
sion in January. Now in case you think I
am trying to make the entire FCC deal
look like a bigger problem than it was,
the trade press reported that Apple®
requested 3 months additional time to
meet the requirements for the Apple II®
and Heath® (Zenith®) asked for 6 months
and they are in the TV business! The FCC
gave them both 3 months to get certified
or stop production. So for those of you
who have asked for some sort of retrofit

kit because your Model I is interfering with
your TV set, all I can suggest is that you
turn off the TV or the Model I. Seriously, if
you do have that problem the best solu-
tion is to increase the TV set signal. Put up
a good new outside antenna with quality
lead-in. If your set is old, especially if it is
a tube set, have it serviced and aligned.

A lot of your letters asked about the
future of the Model I peripherals. The FCC
granted us the right to continue to sell the
expansion interface and disk drives for
the Model I to support the current Model
I owners. Those, and almost all other
Model I items will continue as long as
there is demand. Software? Virtually all
the new software in the works for the
Model III will be Model I compatible so
you will see lots more software including,
finally, a good low cost disk editor/
assembler.

Another subject that generated a lot
of mail was our decision to go subscrip-
tion for the newsletter. All such letters got
the same reply. In fact we had so many
we used a form letter on Scripsit and a
Model II. Here are the reasons:

1. About 0.8% of the U.S. popula-
tion moves every month. Or almost 10%
per year. People also die, sell their TRS-80
or just don't want the Newsletter. Sub-
scriptions give us a way to keep the mail-
ing list clean and not just forever growing
larger and larger.

2. By charging for the subscription
we will be able to mail subscribers by first
class. This will insure that those who want
the Newsletter will get it and quickly The
first free year will not be by first class but
if that is important you may subscribe
early.

3. As you have noticed, the Newslet-
ter is no longer an advertising piece. We
will announce new-product availability
that we feel is of interest, but that will not
be the reason for the Newsletter.

By the way, our largest two compet-
itors in small computers do the following:
one has no newsletter and the other
charges from day 1. So you get ours free
for one year and have plenty of time to
decide if you like it. If you don't, don't sub-
scribe-, it's still a free world, at least in the
USA.

For all you Model II owners who
have, by now, been totally confused by
1.2a and 2.0a, many thanks for your
patience. I would like to tell all the TRS-80
owners about what happened as it illus-

trates just how crazy the computer biz is.
I'm sure most of you know that the
microprocessor has a lot of logic in it to
interpret the commands it receives. You
may not know that a lot of other chips
also have imbedded logic or microcode
and are also processors of a type. For
example, in the Model II, the keyboard,
video, serial ports and the disk controller
are all run by their own intelligent proces-
sor IC's which are big chips called LSI
devices. These are very complex devices,
some much more complex and expen-
sive than the Z80A microprocessor.

As with all complex IC's, there is
always the chance that some of the code
is incorrect and that the IC will not, under
some circumstances, do what the man-
ual says it will do. If you start to get the
idea that microcomputers are designed
by the semiconductor manufacturers,
you are not far wrong. Anyway it seems
that the disk controller IC in the Model II
had a very obscure fault. By very obscure
I mean that none of our software ever
caused the fault to be found in over a year
of Model II production, nor did any other
users of the same IC find the fault. Enter
Model II Accounts Receivable (26-4504),
our first COBOL program. During many
hours of testing it always worked here
but, once it got to you, all of a sudden the
Model II started producing an error mes-
sage "sector not found." What that means
is that the computer can't find the data it
wrote out to the disk. Result here, PANIC!
To compound the problem our engineers
and software people, who worked a lot of
overtime on this one, found that the data
was on the disk but the controller for
some reason could not find it.

After several days we had to con-
clude that TRSDOS was not at fault, nor
was our COBOL, it was the Model II itself
and most likely the disk controller IC. At
this point our supplier of the controller IC
sent a crew down to Fort Worth with
orders not to return until the problem was
solved. Well they found the problem and
announced that, sure, they could remask
the chip and make new ones — only it
would take about 6 months. They then
sat down with our system software peo-
ple and worked out a software fix for the
hardware problem and we released
TRSDOS versions 1.2a and 2.0a. The final
decision on what to do and how to do it
occurred December 24, late in the after-
(Continued on page 4)

Radio /haeH — The biggest name in little computers

©

VieW 7tll (from page 3)
noon and long after we all had promised
to be home. Well no one ever said Mur-
phy's law respected Christmas.

For those of you who do not own
Model II's, you might be interested to
know that we mailed every owner a new
Accounts Receivable disk and made the
"a" versions available, free, to every
owner. And those of you who had to wait
for your new disk drive Model III (and I
hope you have it by now), might be inter-
ested to know that the wait was partly
caused by another version of the same
disk controller that had its own problem
and it did require that the chip be
replaced.

So if any of you want to go into the
microcomputer business, do it with your
eyes open; there are a lot of mine fields
out there. Until next month.

PRINT ©Problem

Mr. Dave McGlumphy sent us this
information about a problem he had run-
ning BASIC programs on two different
Model I's. Here is that portion of his letter-.
". . . Several months ago, 1
'upgraded' my Model I 16K Level II to the
'NEW' ROMs from the 'OLD' ROMs. I sub-
sequently wrote a couple of BASIC pro-
grams which ran fine on my machine but
wouldn't fly on machines with the 'OLD'
ROMs because of a syntax error on
PRINT® statements which occurred
when I used a SHIFT @ accidentally
SHIFT @ was OK on the 'NEW' ROMs but
not acceptable on the 'OLD' ROMs. I
could have gone through the program
and manually fixed each syntax error as it
occurred, but since this particular pro-
gram had quite a number of occurrences,
I used the following statement to fix all the
errors at once:
FOR J= 17123 TO

PEEK(iGS33>+
256* PEEK(13G34) s
IF PEEK(J)= 178 AND
PEEK(J+1)= 3G THEN
POKE J+l >64s NEXT
ELSE NEXT
"Notice that there is no statement
number because this one-statement pro-
gram is to be executed immediately just
one time. 17129 is the address of the
beginning of the BASIC program with the
errors. 16633 and 16634 contain a
pointer to the end of the BASIC program,
so the FOR/NEXT loop starts PEEKing at
the beginning of the BASIC program and
continues to the end of the BASIC pro-
gram. 178 is the token for 'PRINT; and 96
is the decimal value of the ASCII @ when
it is shifted. 64 is the decimal value of the
unshifted @, and since that is what I really
wanted in my program, that is what I
POKEd into memory . . ."

Double Precision Square Root

Here is a letter from George R. Mabry about a double precision square root routine.
I tested the routine and found that I consistently got 15 digits of accuracy.

"When taking the double precision square root of non-perfect square numbers with
my TRS-80 Model I system, it was discovered that the result was accurate to only about
7 or 8 decimal places (Note: SQR is a SINGLE precision function. Ed.) The enclosed
subroutine, however, will yield a double precision square root that has no more error
than 1 part in 16 decimal places.

"The subroutine is based on the following equation:

(1) (B# + X#) 2 = A# where B# = SQR(A#)
Expanding equation (1) gives:

(2) ((X#) 2 + (2*B#*X#) + ((B#) 2 - A#)) =

The application of the quadratic equation to (2) gives the following:

(3)X#= (SQR(A#) -B#)

The computer solution of (3), however, yields a value of for X# since the two
terms on the right side of (3) are identical. If equation (2) is rewritten as follows:

(4)X#= (((A# - (B#*B#))/(2*B#))~ ((X#*X#)/(2*B#)))
then X# can be computed by successive approximation. The first approxi-
mation is:

(5)X#= ((A# - (B#*B#))/(2*B#))

The final approximation is:

(6)X#= (X# - ((X#*X#)/(2*B#)))

The final square root is:

(7)B#= (B# +X#)

Here is the program:

1000
1010
1020
1030
1040
1050

10G0

REM* DOUBLE PRECISION SQUARE ROOT *

REM* INPUT A# t OUTPUT B# *

REM* SCRATCH PAD VARIABLE - X# *

IF A*<>0 THEN 1050

B# = 05 RETURN

B# = S0R(A#)s X#= <(A#- <B#* B#))/

RETURN

( (><## >(#)/ (2* B#) ) ) : B# =

(2* B#) ) s

Model I/III
Graphics Routine

Here is a Graphics routine for a Line
Printer II, sent to us by Alan JefferY Joseph
of Fairhaven, MA:

10 CLEAR 100

20 FOR Y=0 TO 43

30 FOR >( = TO 73

40 IF POINT (X>Y> THEN

B$= B$+ CHR$(127) ELSE

B$= B$ + " "
50 NEXT X
G0 LPRINT B$
70 B*=""
80 NEXT Y

Mr. Joseph comments that "With this
program all graphics in the first 80 spaces
of each Ene go to the LINE PRINTER 2,

Moddl/m

The crew in the back room who
designed the enhancements to Model III
TRSDOS and Disk Basic didn't take our
"biggest name in little computers" trade-
mark too seriously. They keep adding
"big computer" (synonym is costly) fea-
tures that make our little computers think
big (but cost less).

RadM Hiaei— The biggest name
in little computers®

These new commands can be used
to design a business application that is
"friendly" for an operator. For example,
they can help with error situations
(ERROR), protect disks and programs
from incorrect commands (WP), offer
assistance (HELP) and more. Whether
you are writing a program for entertaining
friends, for sale in the market place, for
your business or someone else's you will
appreciate these tools to help "bomb
proof your programs from even the
most novice of users. Some of the newest
additions are great tools to make pro-
gramming faster, and more fun.

Let's finish last month's discussion of
the additions to DISK BASIC first, and then
begin with TRSDOS. CMD"A" is new and
is similar to CMD"S" which returns to
TRSDOS from BASIC, however it also dis-
plays an "OPERATION ABORTED" mes-
sage to let the user know what is going
on. CMD"B" let's you protect a program
from being interrupted by the BREAK key.
The BREAK key is ignored unless cas-
sette, printer or serial I/O is underway.
Use CMD"C" to compress your program
and save disk space by deleting your
choice of all remarks, all spaces or both.
Try CMD"D" to examine the directory for
any specified drive without exiting BASIC.
It works for unprotected, non-invisible
files. If a TRSDOS error condition occurs
use CMD"E" to display the last error and
remain in BASIC. CMD'T" returns a
"STATUS" byte whose value depends on
the type of printer in use and its status at
the moment. Use CMD'T" to test for a
printer that is busy, or out of paper and
either stop the program or tell the opera-
tor to regain control with the BREAK key.
Here is an example of Model Ill's LIB

APPEND ATTRIB

AUTO

BACKUP

BUILD CLEAR

CLOCK

CLS

COPY CREATE

DATE

DEBUG

DIR DO

DUAL

DUMP

ERROR FORMS

FORMAT

FREE

HELP KILL

LIB

LIST

LOAD MASTER

PATCH

PAUSE

Product Line Manager's News

PROT PURGE RELO RENAME

ROUTE SETCOM TAPE TIME

WP

ERROR — You can pay extra for a

"big" computer and big reference docu-
ments to look up the meaning of error
codes or with our big "little" computers
simply type in ERROR xx where xx is any
of the 41 TRSDOS error codes for an
explanation.

ROUTE — We talked last month
about initiating I/O routing from MODEL
III BASIC Use it from TRSDOS also, for
example, to route keyboard input directly
to a printer.

CREATE — Increase the speed of an
application that is dynamically allocating
disk file space by using this command to
first create and then pre-allocate a file for
the size you need. Specify the logical
record length based on the number of
characters and the number of records
needed.

FORMS — Set printer parameters for
line width to provide for continued print-
ing on the next line when a print line
exceeds the width of your printer, and set
the lines per page counter. The lines per
page and number of lines printed infor-
mation can be used by your application to
handle Top-of-Form, etc.

MASTER — If your application con-
sistently accesses a drive other than drive
then assign that drive as the Master
Read or Write drive to speed up file
searching. Then all file searches will begin
with the drive you have specified.

SETCOM— For RS-232C serial com-
munications use this command to initial-
ize the RS-232 to the word length, baud
rate, number of stop bits, and parity for
your communications needs. We have
included the listing of a simple terminal
program in the manual for you to get
started with or you can purchase our RS-
232 Communications Software Package
(26-1149) or Videotex (26-2220).

PATCH — There is no need to reas-
semble your machine language programs
when you want to make a change, this
command lets you alter disk programs or
data files directly. If you are programming
in machine language you will wear this
one out. Otherwise chances are you
won't use it unless we release modifica-
tions to TRSDOS, add a driver routine or
make available some other routine. If we
publish a change for use with the PATCH
command then there will be no need to
obtain another media and possibly trans-

fer files to take advantage of that particular
modification. In these cases we will pro-
vide instructions on how to implement
the change.

TAPE — If you have added a disk to
your system and want to use the software
you have or you are still going to be work-
ing with tape on your Model III Disk Sys-
tem then use this utility to transfer
machine language program files from
Disk to Tape, Tape to Disk, or Tape to
RAM. Simply specify the source and des-
tination choices. As an example TAPE
(S = T,D = D) would transfer a program
from tape to disk.

HELP — This automated Model III
TRSDOS reference card responds with
the syntax formats, definition of the
TRSDOS commands, and explanation of
the abbreviations. If you can't remember
the command you need then HELP will
default to a list of all available TRSDOS
commands.

WP — Can't find a write-protect tab?
Have your application start by execut-
ing a DO file (I will cover this capability
later) to call on this command first off. The
drive you specify will be software write-
protected. This works for any one drive
and will not leave to chance your direc-
tions to a user to protect his program or
data files with a write-protect tab.

CLEAR — Depending oh the options
you select, this command will:

• Zero user memory

• Clear the display

• Un-protect all user memory

• Reset the stack

• Reset I/O drivers

PURGE — Quick and accurate dele-
tion of multiple files is easy with pijpQ£
Filenames vM be displayed one at a time
with a (Y/N/Q) ? option.

DUAL — This is great for debugging
software, creating an application audit
trail, or documenting your programs. All
operator dialog is captured by copying
video output to the printer. If you ever find
an application bug (won't ever happen)
use it to document what is happening so
we can better understand your problem.

RELO — . Loading a program into a
different memory address is as simple as
specifying the file and the hexadecimal
number referring to the new address.

CLS — What can I say? It clears the
display It would be used for example to
make sure that someone doesn't see a
password you have just entered.

(Continued on page 6)

Radio /haeH— The biggest name in little computers

©

MOCICI I/III (from page 5)

There are some new TRSDOS commands left to cover
including the DO, and BUILD capability, other TRSDOS and Disk
BASIC information, lots of news, software applications and lan-
guages to tell you about. Most affect both Model I and Model III
users so keep in touch, I will start on these topics next month.

Model I/III Bugs, Errors
and Fixes

In-Memoty Information (26-1508)

In version 3.0 (for Model I and III), when entering data
(cards) and approaching the end of available memory, all data will
be lost if another card is entered and the "BYTES FREE" is less
than TWICE the card length.

The program will accept the information, but then display the
number of bytes free for about three seconds, indicate "OUT OF
MEMORY" and execute a total re-start, as if beginning the pro-
gram from scratch.

On page 7 of the documentation, there is a note that states
the following:

Note: If the BYTES FREE value drops below the CARD
LENGTH value you can't add any more records.

Please change this line to read:

Note: If the BYTES FREE value drops below two times the
CARD LENGTH value, you can't add any more records; to do so
will result in loss of all data (execution of (R)ESTART).

Accounts Payable (26-1554)

During End-of-Period processing (in VERSION 3.0 only), an
error code 5 may occur in line 45. To prevent this, change lines 45
and 151 of the "PROCESS" program to read:
45 w# = ABS(N#)*100:W#= INT(W#* 10(300 +

♦5D0)/ 100D0S V$=

X=W#/ Dl#i

W#=W#- )■(* Dl# s 0$ = y$+ CHR$()<- (N#<0
)* 128) s X=W#/ D2#s W#=W#- X* D2#;
U$=0$+ CHR$(X)s X=W#/ D3#s W#=H#- X*
D3#; U$=0$+ CHR$(X)+ CHR$(N#): RETURN
151 PRINTS PRINT CHR$(30)? "UNEXPECTED

ERROR CODE"; ERR/ 2+ 1? "IN LINE'S

ERLs GOSUB 65 z END

Accounts Receivable (26-1555)

If you are using the 3.0 VERSION of accounts receivable
under the three drive option, you will encounter a BAD FILE
MODE error in line 628. To prevent this error from occurring, the
following changes need to be made to the "SETUP" program:

Change lines 220 and 880 to read:

220 FL=is GOSUB 280s R$= IN$s IF CFO0
THEN 220 ELSE IF R*<>"Y" AND R$<>
"N" THEN PRINT CHR$(8)5; GOTO 220

880 PD=2s PC=500s PT=2500; IF Q$="M"
THEN ON ERROR GOTO 895s KILL PT$s
PT$= LEFT$(PT$ ,LEN(PT$)-1) +"2"s
CLSs PRINT@458* "INSERT DATA DISK IN
DRIVE 2 AND PRESS < ENTER)- "s ELSE
GOTO 890

Notice that we removed the end of line 220, and added a
statement to the end of line 880. You also need to add the follow-
ing line:

225 IF R$="N" THEN GOSUB 5B0s IF Q$="I"
THEN ZX=0: GOTO 80

Also in Version 3.0, there is an extra quote mark ( " ) at the
end of line 1590 in the "ARS" program. This extra quote can cause

an error code 2 to occur during posting. If you will eliminate the
last quote mark in line 1590, you will eliminate this error.

Business Mailing List 26-1558

The following procedure will allow you to recover and re-
index Mailing list data, in versions prior to 3.0 only, which has
been lost due to a system failure or an abnormal program exit.
Note: this procedure will also "recover" items which were deleted
if the space was not re-used by the program.

1) Enter the following program module:

4999 'RECOVERY

5000 CLSs N=0s TN=is F=0

5005 PRINTTAB(20) "** FILE RECOVERY **"
5010 FOR Q=0 TO CPs O(Q,0)=0; O(Q,1)=0;

NEXT
5015 PRINT@32(3 >"** RECORD NUMBER : n N
5020 N=N+ls J=Ns GOSUB 1840s GOSUB 1900s

GOSUB 1910
5030 IF El*< CHR$(32) OR E0*> CHR$(127)

THEN 5100
5040 NS=ls GOSUB 3210s TN=TN+1: EL$=E1$
50G0 IF N<CP THEN 5015
5100 GOSUB 1790
5110 PRINTS PRINT" > RECOVERY COMPLETE -

PRESS < ENTER > " 5
5120 GOSUB 1460s GOTO 210

2) Save the module using the following BASIC command:
SA0E n REC00ER/ASC'SA (ENTER)

3) Type: LOAD" MLS"

(ENTER)

4) Type: MERG E"RE C00ER/ASC
5) Type: RUN (ENTER)

(ENTER)

6) When the Mailing List Menu appears, press the (BREAK)
key.

7) When the screen shows "READY", type: GOTO 5000
(ENTER)

8) The system will examine your data files and retrieve, re-
sort and index all the valid data found. When this process is com-
plete, the screen will show : "RE COVERY COMPLETE -
PRESS ENTER " ♦ Press (ENTER)

9) The Mailing list Menu will appear. Press the § key to exit
the program immediately.

1.0) Make BACKUP copies of your "recovered" disks. Exam-
ine the data carefully before copying onto your original disks. If
the data is not correct, try the operation again.

Tiny Pascal (26-2009)

You should be aware that in mathematical calculations the
largest value you can work with is 32767. There are two correc-
tions that need to be made on page 9 of the Tiny Pascal manual:

OUTP(a,x) Outputs the value x to port a. This is the opposite
of what the manual says.

SQR(exp) returns the square of exp, not the square root.

FORTRAN— Model I (26-2201) and

Model II (26-4701)

The FORTRAN User's Manual (Page 19 for Model I, Page 9
for Model II) indicates that the default logical record length (LRU
for a CALL OPEN statement is 128 bytes. This is incorrect.

If a programmer does not specify a LRL in the CALL to the
OPEN subroutine, no error message is generated by the compiler,
linker, or run-time package, and the LRL which is produced is
unreliable and may vary from run to run. The format of the rec-
ords written to files opened with no specified LRL is unreliable.

Solution: ALWAYS specify a LRL when using the CALL OPEN
statement.

This month's article for the Educa-
tor's page is written by Dr. Lee Droege-
mueller, Superintendent of Independent
School District 196 in Rosemount, Min-
nesota, a suburb of Minneapolis. Dr.
Droegemueller has been an advocate of
microcomputers for computer literacy for
all students as well as administrative
applications. Under his leadership ISD
196 has been a frontrunner in developing
and implementing new applications of
microcomputers in education.

ENROLLMENT
REPORTING USING
VISICALCT

DR. LEE DROEGEMUELLER
SUPT. OF SCHOOLS
ROSEMOUNT, MINNESOTA

The Rosemount School District
covers approximately 110 square miles of
south suburban Minneapolis and St. Paul,
Minnesota. The district has a total of ten
elementary schools, three middle schools
and two high schools. It is located in a fast
growing area, with student enrollment
increasing from 8,500 in 1975 to 12,500
in 1980. This growth has caused the
opening of six new school buildings since
1976. The growth and additional schools
resulted in attendance boundaries being
changed each year. Classroom enroll-
ment also increased during the year, with
the result that rooms had to be divided at
midyear.

One of the major problems caused
by this continuing growth has been that
the pupil/teacher ratio increases signifi-
cantly during the school year. At the
beginning of the school year, the admin-
istration allocated staff positions for these
increases, and when the pupil/teacher
ratio dictated, these new staff positions
were to be filled. To reassure the Board of
Education, the public, and staff that over-
crowding would be promptly detected
and alleviated, a timely, concise, accurate
report had to be developed to allow us to
monitor the pupil/teacher ratio.

The information needed at the ele-
mentary level was different than that
needed at the secondary level. At the ele-
mentary level statistical data was needed
by grade which included pupil/teacher
ratios, change data, and summary infor-
mation for each building. Only summary
data and changes by building were

Education

Educational Product's News

needed and reported at the secondary
level. Summary data on student enroll-
ment for the district was accumulated by
individual grade. It was further consoli-
dated by elementary, middle and high
school. A special pupil weighting formula
was produced which related to budget
reports.

Attempts at doing this report with a
calculator, paper, pencil and typewriter
were frustrating. There were 600 com-
bined entries and calculations. To further
complicate the task, kindergarten children
could only be counted as half because
they attended school only half days.
Grades seven through twelve had to be
given a factor of 1.4 for state aid revenue
projections. With these and other factors
involved, the probability of a typing or cal-
culating error was always quite high.
Many hours were spent each month pre-
paring this report and the question of
accuracy always remained.

The overview of the VISICALC pro-
gram from Radio Shack stated that it
addressed problems which needed
paper, pencil and the calculator to solve.
Due to the matrix configuration and the
previously stated conditions, VISICALC
appeared to be a natural solution to the
problem. The ease of use of the manual,
and the computer data displayed on the
monitor so that it could be seen just as it
would be printed, were a great help.
Three aspects of VISICALC which made
solving this problem easy were the ability
to set row or column recalculation, the
automatic or manual recalculation option,
and the order of recalculation. The prob-
lem was reworked several times so that
more information could be reported and
memory use could be reduced.

The new report provided informa-
tion on elementary school enrollment,
including the grade, number of students,
number of teachers, average pupil/
teacher ratio by class, monthly change of
the number of students by grade and
summary data by building. Similar detail
was required for the secondary schools.
Figure 3.

DISTRICT

District summaries included changes in
enrollment by grade, the calculation of
weighted pupil units for budget projec-
tions analysis and total enrollment sum-
maries. Sample output is shown in Fig-
ures 1, 2 and 3.
Figure 1.

*

CEDAR

PARK

*GRADE

STDS

STAFF AME

CHG

* KDG

85

1

.5 28.

33

G

* ONE

84

3 28.

00

* TWO

81

3 27,

00

2

* THREE

98

3

♦ 5 28

00

G

* FOUR

122

4

♦ 5 27

11

-1

* FIME

#

113

4 28

25

6

* TOTAL

583

19

.5 27

72

19

* SEP80

550

19

.5 2G

23

33

Figure 2.

SUMMARY

ONE YEAR

GRADE

^

1980-81

SEP 79

CHG

* KDG

978

922

5G

* ONE

951

900

51

* TWO

973

348

25

*THREE

980

1108

-128

* FOUR

1189

1150

19

* FIME

#

1192

1017

175

* TOTAL

S243

8045

198

PUPIL UNITS

(PU)

GRADE

1980-81

SEP 79

CHG

* KDG

489

4G1

28

* ONE

951

900

51

* TWO

973

948

25

*THREE

980

1108

-128

* FOUR

11S3

1150

19

* FIME

#

1192

1017

175

*T0TAL

5754

5584

170

There is a great potential for addi-
tional applications of VISICALC in school
reporting. In this particular situation the
elimination of several hours of work, the
increase in reports generated, and the
neatness of formatted printer output all
underscore the convenience of VISICALC.
The VISICALC enrollment report has
reduced the number of questions at
Board of Education meetings, made com-
parisons easier for the public, helped prin-
cipals answer questions on class size, and
improved administrative decision
making.

19G SUMMARY

* 1980-81 SEP 79 CHG 80-81PU SEP 79PU CHG *

* TOTAL K-5 S243

* TOTAL MIDDLE 2952

* TOTAL SENIOR 32G7

G045 198
2G82 270
319G 71

5754

3718

4573,8

5584 170
3374,4 343*G
4474*4 99,4

#
#

* *

* GRAND TOTAL 124G2 11923 539 14045,8 13432,8 G13 *

Peripherals

Product Line Manager's News

This month I will keep the promise I
made last month but with a little hedging.
So much is happening that there will be
room this month to outline only a part of
the promised new comprehensive printer
code standard (What I will show you is a
portion of the Graphics control standard).
I'll start, in great excitement, with some-
thing entirely new. We will be announcing
a new printer soon: line Printer VII. If the
name isn't surprising, the printer is! This
machine is Radio Shack's first dot-matrix
machine to offer full graphics capabilities.

Designed with the color computer in
mind, the unit includes the standard par-
allel interface for use with Models I, II, and
III and features, in addition, a four pin DIN
connector for use with the serial port of
the Color Computer. The price of this little
gem (26-1 167) is only $399.00!

This is a full performance printer; no
narrow or strange paper for this fellow. It
prints 8 inch, 80 column lines on regular
9W tractor paper (26-1423 — $7.95).
Here is a run-down on its features:

Graphic or alpha-numeric characters can
be intermixed on the same line

5x7 matrix characters or 7 bit dot
addressable graphics patterns

Full size sample of LP VII graphics

X

Switch selectable input — parallel or serial
(7 or 8 bit — 8 bit required for graphics)

Adjustable tractor 4Vfc to 9 l /z inches

6 or 9 (graphic mode) lines per inch

30 CPS speed

The printer uses a unique single
hammer system. The carriage move-
ment, the motion of the hammer, and the
revolution of a ridged platen accomplish
all the printing wonders.

Line Printer VII will produce all the
ASCII standard alphanumeric characters.
Once set in the graphic mode, however,
any code except those for special control
and graphic information will be ignored.
Special commands move the carriage to
any of the 480 dot columns available in
the 8" line. The impression produced by
the printer in any dot column is deter-
mined by sending an 8 bit binary code.
The 8th bit (most significant) signifies
graphic information. The other seven bits
(set to "1" or "0") correspond to the col-
umn pattern placed on the paper. Another
command allows repetition of patterns
for code economy

In this manner, the programmer can
control all the dots produced on the page
to a density of 3780 dots per square inch!

By the way, the current version of the
Color Computer produces 7 bit output.
Radio Shack will provide a special driver
program which will allow the Color Com-
puter to send the 8 bit characters,
required for graphics, to the printer (700-
2013).

Here are the line Printer VII graphics
codes in the Radio Shack Standard:

DEC
18

10
13

26

28,N

HEX
12

0D J

1A

1CN

27.16.BB 1B,10,BB

FUNCTION
Set Graphic
Mode

Normal Line
Feed (CR plus
LF) prints buffer
and generates
new line.

C/R— Prints

buffer and
issues CR but
noLF.

Repeat the next
dot pattern
N times.
Move carriage
to dot column
BB (9 bit value).

(Continued on 18)

1.0

0.5

0.0

/

/

/

/

V

/

A

/ \

/ \

i \

•i

\

\

I

' V

\

i

-0.5

-1.0

/ / \ \"l

.{.... \l80. . . \ ■ • .360/ . . .

/ \ \/ /

A

IA

40

/

■/"

8

By now, I should hope that you have
read, seen, heard, or talked about the
"new" kid on the block. That's right, the
TRS-80 Extended Basic Color Computer
(catalog no. 260-3002 $599.00). (Looks
just like the standard color computer,
doesn't it. Well, what you can't see is what
makes it so fantastic!) If you haven't, I'm
going to tell you a little about it now —

As is the format of this column, I
want to clear up some of the errata before
we proceed. The TRS-80 Computer Cat-
alog No. RSC-4 was a little misleading
(. . . of course our new RSC-5 is available
now...) in the description of the
Extended Color BASIC (available in the
26-3002 or as a kit (26-3018 $99.00)
which requires 16K RAM (26-3015
$119.00) and installation, etc.). To quote
from the catalog "You can save an image
from the screen, display a predefined
image, "zoom" the graphic image "in" or
"out" . . . rotate the image, move the
image from one area of the screen to
another,". That's what it says . . . now here
is what you can really do with Extended
Color BASIC: "You can save an image
from the screen, . . ."; What you can do is
save the data which generates the graph-
ics (if your software is set up to use data
statements) so they can be read back in
whenever you wish to recreate the graph-
ics. M . . . display a predefined image,
"zoom" the image "in" or "out"": What
you have the capabilities of doing with the
Color Computer's Extended BASIC is
choosing from up to eight screens. Think
of a large note-pad with only V& of it
showing through a "window." If you
move the window, you see a different
area, or if you move the window farther
away from the pad, you see more sec-
tions of it. Get the picture? Well, the
Extended BASIC Color Computer works
in a similar way; you write or draw on one
section not being displayed, then you dis-
play it. Displaying a predefined image is
true. However, "zooming" is not. It is pos-

Color Computer

Product Line Manager's News

sible to do, but not easily What you have
to do is redraw the image over and over
again, changing the location of the image
on one of the screens not being currently
displayed. "... rotate the image . . ."; this
would be accomplished much the same
as "zooming" would be handled. "...
move the image from one area ... to
another . . .": What you are really doing is
drawing the graphics on one of the
screens and changing the window
through which you are looking at the
graphic.

Confused? Well, read on and maybe
things will get clearer

Let's get a little common ground
between us before we get into the thick of
things: The Extended BASIC version of
the Color Computer contains all of the fea-
tures of the standard machine with some
very interesting additions. First off, the
computer has 16K of RAM of which a
maximum of about 14.5K is usable for
programming (the balance is saved and
used for video, BASIC, and graphics). You
can allocate more memory for graphics if
your creations need it or if you're going
into higher resolution (more on that later).
All of the accessories for the standard
Color Computer will work on the
Extended BASIC machine, including the
Joysticks and ail the program paks.®
Some of the program paks will even
appear to be smoother in operation
(Quasar Commander especially) of the
graphics because of the additional mem-
ory. Besides all that, you get EDITing,
which means not having to retype that
line when you make a mistake-, multi-
character string names (first two charac-
ters significant) and easy access to higher
resolution (there's that word again) graph-
ics. It's not just the fact that the Extended
version offers higher resolution graphics,
it is HOW the higher resolution graphics
are offered. What this version of BASIC
has are one line instructions to DRAW a
line from point A (x,y) to point B (x,y),
make it either the foreground or back-
ground color (yes, you can set what fore-
grounoVbackground colors will be), make
that line the diagonal of a box and even fill
that box with either the foreground or
background color. Just ONE statement
does it all! The program statement is . . .
LINE. There is another one line statement
which will draw a CIRCLE. All you need to
tell it is where the center is (x,y), the
radius, the color, aspect (optional), start-

ing and ending points (optional — -in case
you don't want a full circle, only a partial
one). Again, just ONE statement does all
that! That program statement is . . . you
guessed it . . . CIRCLE. There is a PAGE
function which lets you look at one of
eight pages of graphic memory (remem-
ber that note-pad and "window").
Depending on which graphics resolution
mode you are in (there are 4 to choose
from), you will see all or part of that page
(maybe that's where they got the "zoom"
idea). Speaking of graphics modes, you
can select from low resolution (at last, an
explanation, the number of distinct points
on the screen) of 2048 points (64x32) up
to 49152 points (192x256, even though
the RSC-4 catalog states 196x256 p.29).
High resolution means you can "turn on"
100 distinct points on the screen and
those points won't take up more than a l /z
inch square on a 13" monitor. Do you
remember the program in the back of the
Level I, Model I BASIC manual, the one
about termites? The one that takes about
15 minutes to completely clear the
screen? Well, if you tried something like
that on the Extended BASIC Color
machine, you might be there awhile,
waiting for those "termites" to eat up the
screen. It would almost be like having a
pest controller on your team!

Now, a few more brief definitions of
some of the other commands you'll find
in Extended Color BASIC:

PCLEAR x: allocates x (1-8) number of
pages of memory for graphics.

PMODE x,y: where x (1-4) is the graphics
mode and y (1-8) is the starting page of
memory you wish to display The graph-
ics mode and the memory starting page
are dependent on each other and the
number of pages you have PCLEARed.

SCREEN x,y= where x (0-1) is either for
text display or 1 for graphics display and
y (0-1) is the choice between two sets of
four colors. For y = 0: green, red, yellow,
blue; for y= 1: buff, cyan, magenta,
orange. These colors can also be adjusted
by using the color and tint controls on the
TV set.

One quick note here: higher resolu-
tion graphics and text cannot be shown
simultaneously on the screen.

PCLS(x): used after you have selected
your starting page for graphics, it clears
the screen, using the value color of x
(1-8). (Continued on page 17)

Model n

Product Line Manager s News

Another hint for PROFILE-II users. Would you like to create
your own custom MENU? Would you like to pass the program
some parameters and get you or your secretary away from
answering the FILENAME and SCREEN NUMBER question every-
time (sometimes getting the wrong screen or report format)?

A simple custom MENU with a short description of each of
the screen or report formats that you use will eliminate trying to
remember which format is which.

Try this routine on a BACKUP of your PROFILE disk . . .

First, you must still have BASIC on the disk. Second, rename
the current MENU to X by typing RENAME M TO X and press-
ing GEnTER) .

You must create a machine langua ge pro gram with DEBUG.
From TRSD OS, typ e C L E A R and press (ENTER) , now type DEBUG
N t press (ENTER) , type D E B U G and (ENTER) . Press (M) and enter
E 0(30 for the address. Press the (FT) key and the cursor should
be in the upper left hand comer of the screen at the first set of
double zeros. Enter the following codes exactly. You do not have
to press the space bar.
21 09 E0 SB 0A 3E 28 CF
C9 42 41 53 49 43 20 4D
45 4E 55

Double check the entries you made, using the arrow keys to
position the cursor and make any corrections.

Press the (F2) key then the LETTER ®. You should be back
in TRSDOS. Now you must save this program, type
DUMP M -CSTA RT = E000 END = E012>
and press (ENTER) Build a DO file by typing BUILD USER
(ENTER) . In the DO file, type BASIC MENU and press (ENTER)
three times. This will store the DO file with a filename of U SER.

When you return to TRSDOS READY, type BASIC CENTER)
and you are ready to create the MENU. I will give you a sample
menu using "DJS" for the example file names (lines 200 thru 230).
In all cases, use the file name you normally enter when using
PROFILE but followed with enough s to make it 8 characters
long.

5 GOTO
7 SAME
10 CLS

10
"MENU"

END

20

30

40

50
S0
70
80
30

100

110

120

130
200

210

15)

PRINT@(3

RECORDS"

PRINT(§(5

FORM) "

PRINT@(7

FORM) M

PRINTGO

PRINTGCli >25)

PRINT@(13 *25)

PRINTi(15 .25)

PRINT@(17 .25)
PRINT@(19 .28) t
IF
CLS
200
270

5) ."1 ) ADD / UPDATE

5) ."2) PRINT FILE (LONG

.25) f"3) PRINT FILE (SHORT

a)

n 5)
!, B)
M 7)
"8)

PRINT LABELS' 1
PROFILE DIRECTORY"
EXPAND FILE"
PROFILE MENU"

TRSDOS"

EXIT TO
"SELECTION
A$="" THEN

A$=INKEY$

A=0AL(A$)

ON A GOTO

250. 2S0.

GOTO 10

SYSTEM "CLERK/EFC {DJS00000

HEADING FOR TOP OF SCREEN}"

SYSTEM "PRINT/EFC -CDJS00000.1

INSTRUCTIONS FOR SORTING}"

110 ELSE

. 210. 220. 230. 240.

1

OR

LABEL

220 SYSTEM "PRINT/EFC {DJS00000.2

SELECTING RECORDS}"
230 SYSTEM "LABEL/EFC -CDJS00000.1

INSTRUCTIONS}"
240 SYSTEM "DIR/EFC"
250 SYSTEM "EXPAND/EFC"
2G0 SYSTEM "X"
270 SYSTEM

If you have more than 9 items in your menu, replac e line
110 with the one below but you will have to press (ENTER) after
your menu selection.

110 INPUT As CLS

Notice the format number in lines 210 and 220. This
answers the question for you when the program asks "Enter For-
mat Number (1-5)."

Also notice that there is no space before the format number
in 200, 210,220, or 230.

Now type GOTO 7, press CENTER) and the program will be
stored on disk with a file name of MENU.

To use this new menu, type (M) from TRSDOS READY, just
as you did before.

A few points about lines 120 and 200 thru 270. For each
item you add in lines 20 thru 90, there must be a corresponding
line (lines 200 thru 270) to execute the command. Each line, 200
and on, contains the PROFILE program you wish to use.

CLERK/EFC is the normal screen program used to enter, add
or update the data. The braces are required, followed by the FILE-
NAME filled to 8 places with zeros. The number (1-5) is the screen
or print format you wish to use.

The statement after the number will be placed at the top of
the screen and can be any instruction or title you wish the opera-
tor to see when using the program. Most of the PROFILE modules
can be passed paramet ers with this method and, another advan-
tage, when you press (ENTER) to exit the module, you will be
returned directly to the MENU.

PROFILE programs that you can execute from the BASIC
MENU are:

CLERK/EFC = Video screens used to add or update your

data files.
PRINT/EFC = Printer formats
LABEI7EFC = Label printing

EXPAND/EFC = Used to expand the number of records
DIR/EFC = PROFILE directory
SELECTOR/EFC = Selects records for merging with other

programs (Continued on page 12)

ygM I found the bug!

10

Pocket Computer

Product Line Manager s News

Well, Spring is about to spring upon us here in Texas and the
weather is just perfect for flying ■ • • which brings me neatly to the
first subject of this month's column, our Pocket Computer Aviation
software package called AVPACKL

This software package became available in February in all of
our stores, under Catalog number 26-3513 and priced at $24.95.
The package consists of one cassette tape with a single program
which fills the entire computer memory (with only 6 steps left!).
AVPACKI is a departure from our other Pocket Computer software
formats in that we have supplied a plastic overlay for the keyboard
which shows the function of the 15 Reserve keys used in opera-
tion of the program, rather than have a menu which would con-
sume too much memory and not allow the incorporation of all
the functions into one load module.

First, let's have an overview of the features of this package.
As I previously implied, the program has 15 functions initiated by
a (§HFT) and then pressing one of the Reserve keys. These keys
cause the computer to perform conversions or calculations
according to the following:

CONVERT

C — Temperature from Celsius to Fahrenheit.
F _ Temperature from Fahrenheit to Celsius.
M— Statute Miles to Nautical Miles and Kilometers.
N — Nautical Miles to Statute Miles and Kilometers.
K — Kilometers to Statute Miles and Nautical Miles.
G — U.S. Gallons to Imperial Gallons and Liters.
B — Imperial Gallons to U.S. Gallons and Liters.
L —Liters to U.S. Gallons and Imperial Gallons.

CALCULATE

A —True Altitude, using Pressure Altitude, Temperature and

Reference Altitude.
V — True Airpseed, using Pressure Altitude, Temperature and

Indicated Airspeed.
X — Mach Number, based on True Airspeed and Temperature.
Z — True Airpseed, based on Mach Number and Temperature.
D — - Off-Course Correction and Drift Angles.
H -—True Heading and Ground Speed with winds.
J — Enroute Winds.

Those of you who are private pilots or who have flown a light
aircraft recently, will recognize that these functions will handle
nearly all of the requirements of visual flight navigation, with the
possible exception of Dead Reckoning (Rhumb Line) calculations.
So, now that we've had our 'pre-ffight,' let's 'take-off and look at
some specifics.

For those not familiar with the Pocket Computer, once you
load the program, everything including your answers and data is
stored in the computer even if power is turned off. Thus, once a
calculation or conversion is completed, the answer is stored in
one of 26 locations in the computers memory. These locations
are listed in Appendix E of the AVPACKI Operators Manual. An
answer or piece of data may be recalled at any time simply by
typing its letter and pressing ENTER.

As an example of the ease of use of these conversions, let's
take the following example:

You've flown your plane down to Puerto Vallarta for a little
vacation and it's time to go have some fun, but you have to fuel
up first. Mexico sells gasoline by the Imperial Gallon and you want
to find out how many gallons (US) you used on the last leg of your

flight. After topping-off your tanks, you find that you used 18
Imperial Gallons and your flight log shows 2 Hours and 50 Min-
utes flying time. Now for some Pocket Computer Power! Turn on
the computer, type 1 8 and press (SHFT) (J). This converts to 21.6
U.S. Gallons or 81.8 liters as shown on the display. Now press ®
(this is the memory locati on w hich stores 'Liquid Measure in
U.S. Gallons') and press (ENTE R). The display will now show
21 t G i 728, the true equivalent in U.S. Gallons. So-far-so-good
b u t now for the tricky part! Your log shows 2 Hours, 50 Minutes
but this 'time' must be in decimal format to allow figuring out how
much fuel you used per hour. The Pocket Computer has a Func-
tion called DEG which we will put to use here. DEG will take an
input of Degrees, Minutes and Seconds in the form 'DDD.MMSS'
and convert it to decimal. Since this conforms to the notation for
time, we will use it to convert our flying time to t he req uired dec-
imal equivalent. Type G/DEG2*50 and press (ENTER) . The dis-
play will show 7*829828235 indicating the number of U.S.
Gallons of gasoline burned per hour on the last leg of your flight.
By now you may be saying 'Run that by again?' . . . OK, here's
what happened. Register l G' contains our fuel used in U.S. Gal-
lons, the slash (/) causes division and the DEG2.50 converts the
hours and minutes to 2.833333333 decimal hours before divid-
ing into the 21.61728 Gallons stored in 'G.' Tricky, isn't it!

This is just one example of the powerful conversion capa-
bilities of this program and the Pocket Computer. Rather than
continue with another example of the Calculations, I am going to
proceed to another topic which will take up the rest of my allotted
space. So, if you are a pilot, or an aspiring pilot, I hope I have
piqued your interest enough so that you will go down to your
nearest Radio Shack and ask for a 'hands on' demonstration. And,
if by chance they don't have this program package yet, please ask
the store manager to order one for you to look at.

My next subject is SOLICITING . . . soliciting SOFTWARE that
is! Yes, we ARE looking for good programs for the Pocket Com-
puter! As you can well imagine, it would be impossible for Radio
Shack to write programs to cover all or anywhere near all of the
application possibilities of this incredible little (BIG) computer. So,
I am asking you, our faithful readers and TRS-80 owners, not only
for ideas for us to look at, but preferably for fully completed Pocket
Computer software for us to evaluate and consider for marketing
through our growing chain of Radio Shack stores and Computer
Centers which now number around 7000! Toward this end, I
would like to outline the following procedures (and facts-oMife of
a big corporation) for your guidance in submitting your program
or idea, to wit:

1) Submit a concise description of the program, what it does,
who would use it and why you feel it would have mass appeal.
State whether or not the program has been copyrighted and
whether or not you've sold copies of it (this doesn't affect our
interest, only the way we must handle it to protect your interests
and ours). Obviously the program must be your own work. Con-
tractually, you will be required to "hold Radio Shack harmless" in
the event of a copyright suit by someone else.

2) Give us time. We often move slowly We will let you know
if we're interested, and arrange to have you send a copy of the
program for more serious evaluation. And above all, you must
realize that there are many reasons why we might reject your pro-
gram . . . poorly written or documented, limited market, poor error
trapping, hard to use, similar to a program now in development,

(Continued on page 12)

TT

Radie /haeH The biggest name in little computers

(TM)

MOClel II (from page 10)

Four of the modules that cannot accept parameters are
EXPAND/EFC, SELECTOR/EFC, DIR/EFC and SELECT/BAS.

One warning and one suggestion.

THE WARNING: Do NOT try to execute either of the DO files
for the LIMITED MENU or the UNLIMITED MENU, this will kill the
"M" program that you created with DEBUG.

THE SUGGESTION: You should not try to execute any of the
"CREATION" programs such as CREATE/EFC or LPFORM/EFC
from this menu. The "CREATION" programs CAN be called but
they CANNOT be passed any parameters and are not normally
used on a day-to-day basis. They can still be executed from the
original menu that you have now renamed "X."

Good luck with your new MENU. It should make using
PROFILE-H a lot more enjoyable.

Model II Bugs, Errors and
Fixes

Patch for TRSDOS 2.0

In the TERMINAL utility, the "G" (Get disk file into RAM) func-
tion, when used with a variable-length record file, will insert 1
extra byte before every logical record.

To prevent this from happening, apply the following two
patches:
PATCH TERMINAL A=3723

F=FE4B28 C=DG5G20

PATCH TERMINAL A=372A

F=0S004E23AFB9C004C9
O474E230DC0E1C3FG32

General Ledger (26-4501)

The Batch Total in a posting summary does not equal the
document balance.

To correct this, Change line 730 of "Txpost" to read:

730 IN#=0s FORQ=0TO NE - 1 s

IF AM # <Q> >0 THEN

IN#=IN# + AM*MQ>
You also need to change line 6730 of the "Txentry" program.
Change this line to read:

S730 IN#=0s FORQ=0TO NE -is

IF AM#(Q) >0 THEN IN#=IN#+
AM#(Q)

Payroll (26-4503)

When preparing checks with either version 1.0 or 1. 1, values
are being rounded improperly Some values are being rounded
with an error of up to three cents.

To correct this problem, change line 820 of the 'INPUT" to
read:

820 R#(I)= INT(R#(I>* 100D0+ + 5D0>/
10000s E#( I)= H*( I )* R*< I ) s
E#(I)= INT(E#(I)* 100D0+ *5D0)/
100D0S GOTO 840

Accounts Payable (26-4505)

There have been several customers who have encountered error
code 5 in the invoice section of version 1 .0 Accounts Payable. The
same error is also encountered in End-of-period processing. To
correct these problems, make the following changes:

12

For invoices, change line 350 of the "APINVCE/BAS" pro-
gram to read:

350 N# = VAL(IN$): N#= ABS(N**)* 100;

N4*= INT(N#* 100D0+ ,5D0)/ 100D0S
g$=" " : ♦ ♦ ♦

The rest of the line is unchanged. Be sure you save a copy of
the corrected program.

For End-of-Period, change line 800 in the "APPROC/BAS"
program to read:

800 M* = ABS(N#)* 100 sH*s= INT(M#* 100D0+
♦ 5D0)/ 10BD0: V$= U ": ♦ ♦ ♦

The rest of this line is unchanged. Again, do not forget to save
a co PY-

POCket (from page 11)

too far from our 'style,' etc. If we reject it, you will receive a form
letter, not an individual reply . . . if you have a 'thin skin,' it might be
better if you don't submit. Incidentally, we like to see programs
which use the full power of the Pocket Computer in order to max-
imize the somewhat limited user memory, the previously men-
tioned AVPACKI program being an example.

3) Be prepared to wait UP TO a year before you see an
accepted program on our shelves. All the testing, editing, debug-
ging and manual writing just takes time!

4) Be prepared to accept the decision of our software evalu-
ation team. Anyone else you write within Radio Shack will just
refer you to them. Their decision is final.

5) If we like your program, we might offer you an outright
purchase price, or a royalty on copies sold. Our royalties are much
like some publishers offer ... not big, but if the package sells, they
can REALLY mount up fast.

Now, if you're still interested, send your letters to:

PC Software Evaluation

Radio Shack
700 One Tandy Center
Fort Worth, TK 76102

Before I close for this month, let me give you a few hints/
ideas which might be helpful in your efforts to write 'mass-market'
software for the Pocket Computer. We view the Pocket Computer
as having tremendous application in a wide range of VERTICAL
markets. By that I mean not only the engineering and financial
disciplines, but areas such as medicine, pharmacology, insurance
(all types), agriculture, photography, meteorology, oceanography
to name but a few. I am sure that with over 100,000 readers of
this newsletter, there must be at least one 'expert' in nearly every
discipline I could name who could provide a good application pro-
gram for the Pocket Computer. In closing then, I would urge you
to give this some thought and if you are not familiar with the
Pocket Computer, stop by one of our stores and get a demonstra-
tion! Until April then . . . more Pocket Power to you.

Radio /haelt — The biggest name in little computers®

STOP THAT OUT-OF-SORTS FEELING

A fast 2D string array Machine Sort — Listing 1

sort

By William Terrell

Many of you have probably devel-
oped programs which included routines
to sort arrays of strings. Unfortunately,
string sorting programs in BASIC are very
slow. The March/April 1980 issue of the
TRS-80 Microcomputer News covered a
number of BASIC sort routines with the
best taking 16 minutes to sort 500 strings.
As a result, when the July 1980 issue pro-
vided a machine language sort which
claimed cut the time to sort to seconds, it
caught my interest.

I quickly keyed in the demonstration
program — a machine language program
poked into memory from BASIC and
invoked by the USR command. It did
everything they claimed. Arrays of 500
strings could be sorted in 4 seconds!

Now I had no excuse for not com-
pleting the many programs which I had
abandoned as impractical due to exces-
sive processing time. But wait! I soon dis-
covered that this program was limited to
sorting single dimension string arrays.
Mailing lists, inventory programs, and the
like required two-dimensional arrays.
Sorting on only one dimension would
completely scramble the data. I was still
without a suitable string sorting program.

Perhaps I could modify this program
to provide two-dimensional array string
sorting capability. The first step was to fig-
ure out how the program worked. After I
had poked the machine language pro-
gram into memory, I loaded and ran my
trust disassembler program. This con-
verts the machine code into assembly
language mnemonics, a set of com-
mands which humans can understand.

After a couple of hours of study, the
basic flow of this program was clear to
me. The number of strings being sorted
and the pointer to the first string were
passed to the machine language program
by the BASIC'S USR command pretty
much as the Level II manual describes.
This data was accepted by the machine
language program and put into storage
locations. Next, the program selected and
compared strings. Sorting was accom-
plished by swapping BASIC'S variable
pointers. I located the part of the program
which did the actual swapping. Now all I
had to do was modify that section to
swap all related pointers at the same time.
A few other details had to be
addressed as well. The program needed
to know how many related data fields
(Continued on page 14)

7EDF

00110

ORG

7EDFH

00120

5 GET 0ARPTR FOR Z(0)

7EDF CD7F0A

00130 ENTRY

CALL

0A7FH

00140

5 LOAD I
SETS

NUMBER OF DATA

7EE2 5E

00150

LD

E>(HL)

7EE3 23

00160

INC

HL

7EE4 56

00170

LD

D ><HL)

00180

5 STORE

IT

7EE5 ED530A7F

00190

LD

CST0RN+1) *DE

00200

5 LOAD
DATA

0ARPTR TO SORTED

7EE9 23

00210

INC

HL

7EEA 5E

00220

LD

E »(HL)

7EEB 23

00230

INC

HL

7EEC se

00240

LD

D *<HL)

00250

5 STORE

IT

?EED ED53F87F

00260

LD

(ST0R0) >DE

00270

;load

NUMBER OF FIELDS

7EF1 23

00280

INC

HL

7EF2 5E

00290

LD

E>(HL)

7EF3 23

00300

INC

HL

7EF4 56

00310

LD

D , (HL)

00320

5 STORE

IT

7EF5 ED53FA7F

00330

LD

(DIMENS) >DE

00340

5 LOAD

POINTER DELTA

7EF9 23

00350

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HL

7EFA 5E

00360

LD

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7EFB 23

00370

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HL

7EFC 56

00380

LD

D*(HL)

00390

5 STORE

IT

7EFD ED53FC7F

00400

LD

(PTRDEL) *DE

00410

5 LOAD

FIELD-FIELD DELTA

7F01 23

00420

INC

HL

7F02 5E

00430

LD

E,(HL)

7F03 23

00440

INC

HL

7F04 56

00450

LD

D>(HL>

00460

5 STORE

: it

7F05 ED53FE7F

00470

LD

(C0LDEL) *DE

7F09 210000

00480 ST0RN

LD

HL >$-$

7F0C 22F67F

00490

LD

(ST0RDE) ,HL

00500 5START

SELECT I

ic COMPARE

7F0F ED5BF67F

00510 CYCLE

LD

DE t(STORDE)

7F13 CB3B

00520

SRL

E

7F15 AF

00530

X0R

A

7F16 CB3A

00540

SRL

D

7F18 3002

00550

JR

NC , BYPASS

7F1A CBFB

00560

SET

7 >E

7F1C ED53F67F

00570 BYPASS

LD

(ST0RDE) >DE

7F20 7A

00580

LD

A >D

7F21 B3

00590

OR

E

7F22 C8

00600

RET

~7

7F23 2A0A7F

00610

LD

HL , (ST0RN+1 )

7F26 ED52

00620

SBC

HL>DE

7F28 22F27F

00630

LD

(ST0RT3) tUL

7F2B 210000

00640

LD

HL >$-$

7F2E 22F07F

00650

LD

(ST0RT2) >HL

7F31 2AF07F

00660 AGAIN

LD

HL , (ST0RT2)

7F34 22EE7F

00670

LD

(ST0RT1) *HL

7F37 2AEE7F

00880 REPEAT

LD

HL#(ST0RT1)

7F3A ED5BF67F

00690

LD

DE t(STORDE)

7F3E 19

00700

ADD

HL >DE

(Continued on page 14)

13

Radio fhaeU The biggest name in little computers

(TM)

(from page 13)

Out-of-Sorts

were being swapped and where the^
were. This information could be passed to
the machine language program in the
same manner as the original program.
Now that I had the concept worked out,
all I had to do was implement it.

Rather than start from scratch, I first
copied the disassembled version of the
original machine language program using
the Radio Shack Editor/Assembler. Since
I expected to have to relocate the
machine code, I assigned a label to each
absolute address. Next, provision was
added to allow the program to accept the
added inputs mentioned above. Finally,
the swapping instructions were expanded
to swap the related string fields at the
same time. I was ready to test it!

For convenience, I loaded the new
machine language program (see Listing
1) into high memory with the SYSTEM
command. The original TRS-80 Micro-
computer News BASIC demonstration
program was then modified to interface
with the new program. Of course, it didn't
work the first time (or the second or third
time either). After a few iterations with the
Editor/Assembler, I had it sorting string
arrays of 100 by 5 size. Sorting time did
not seem to be longer than the original
program. Now all that remained was to
pretty it up and tell the world.

I chose to produce a demonstration
program (see listing 2) very similar to the
original with lots of REMarks so that pro-
spective users can understand how to
adapt the program to their needs. In fact,
I put so many REM's in it that they have to
be deleted to allow the program to run in
a 16K Level II machine. If you do dupli-
cate the whole program for your records,
CSAVE a similar program with the REM's
deleted for running it.

Before loading this demonstration
program, you must protect memory (in
response to MEMORY SIZE?) at 32478.
After CLOAD and RUN, the program will
take a few seconds to poke the machine
language program into the protected
memory space. Then it will ask you:

"NUMBER OF DATA SETS (100 MAX)
YOU WANT?"

As it is presently dimensioned, you
may enter any number up to 100 to rep-
resent the 'rows' of data. Then it will ask
you:

"HOW MANY FIELDS (5 MAX) IN
EACH?"

You should enter any number up to
5 to represent the number of related
'fields' in each 'row.' The computer will
now take from a few seconds up to a
minute or so to generate a random, two-

(Continued on page 15)

oon

— Justin

g 1 (from page 13)

7F3F

22F47F

00710

LD

(ST0RHL) ,HL

7F42

EB

00720

EX

DE *HL

7F43

210000

00730

LD

HL>$-$

7F4S

19

00740

ADD

HL ,DE

7F47

19

00750

ADD

HL *DE

7F48

19

00760

ADD

HL >DE

7F49

E5

00770

PUSH

HL

7F4A

ED5BEE7F

00780

LD

DE , (ST0RT1)

7F4E

210000

00790

LD

HL>$-$

7F51

19

00800

ADD

HL,DE

7F52

19

00810

ADD

HL,DE

7F53

19

00820

ADD

HL*DE

7F54

ED4BF87F

00830

LD

BCf (ST0RV)

7F58

09

00840

ADD

HL,BC

7F59

EB

00850

EX

DE >HL

7F5A

El

00880

POP

HL

7F5B

09

00870

ADD

HL*BC

7F5C

E5

00880

PUSH

HL

7F5D

D5

00890

PUSH

DE

7F5E

0E00

00900

LD

C>0

7F60

7E

00910

LD

A »(HL)

7FB1

47

00920

LD

B >A

7FG2

1A

00930

LD

A t(DE)

7FG3

B8

00940

CP

B

7F64

3003

00950

JR

NC, CLEAR

7F66

0E01

00960

LD

c,i

7F68

47

00970

LD

B>A

7FG9

AF

00980 CLEAR

X0R

A

7F6A

B0

00990

OR

B

7F6B

2819

01000

JR

Z»SKIP

7F6D

C5

01010

PUSH

BC

7FGE

13

01020

INC

DE

7F6F

23

01030

INC

HL

7F70

4E

01040

LD

C*(HL)

7F71

23

01050

INC

HL

7F72

46

01060

LD

B»(HL)

7F73

C5

01070

PUSH

BC

7F74

El

01080

POP

HL

7F75

EB

01090

EX

DE*HL

7F7G

4E

01100

LD

C *(HL)

7F77

23

01110

INC

HL

7F78

46

01120

LD

B*(HL)

7F79

C5

01130

PUSH

BC

7F7A

El

01140

POP

HL

7F7B

CI

01150

POP

BC

7F7C

1A

01160 BACK

LD

A»(DE)

7F7D

96

01170

SUB

(HL)

7F7E

380A

01180

JR

C >P0P

7F80

2053

01190

JR

NZ, FINIS

7F82

13

01200

INC

DE

7F83

23

01210

INC

HL

7F84

10F6

01220

DJN2

BACK

7F86

CB41

01230 SKIP

BIT

0,C

7F88

204B

01240

JR

NZ tFINIS

01250 5M0UE

BACK TO

ZERO COLUMN

7F8A

ED4BFC7F

01260 POP

LD

BC(PTRDEL)

7F8E

AF

01270

X0R

A

7F8F

El

01280

POP

HL

7F90

ED42

01290

SBC

HL >BC

7F92

EB

01300

EX

DE >HL

7F93

El

01310

POP

HL

7F94

ED42

01320

SBC

HL ,BC

01330

5SET

FOR N0» OF COLUMNS

(Continued on page 15)

14

Radio /haelf—— ■ The biggest name in little computers

©

Otlt-Of-SortS (from page 14)

dimensional string array to your specifi-
cation. This slow process is not part of the
sorting routine, but rather a clumsy way
to create some test data for the program.
Next, the computer will ask you:

"SORT ON WHICH FIELD (ZERO IS
1ST)?"

You should respond with the num-
ber of the 'field' in the data 'row.' Remem-
ber that the first field is "0." We're now
ready to start the data sort as soon as you
respond to:
TRESS 'ENTER' WHEN READY?"

This last prompting question was put
in the program so you could start timing
the sorting if you want. As soon as the
sorted string array starts printing on the
video, you know that the sort is complete.
Finally, the computer will display:

TOR ANOTHER SORT ON THE SAME

DATA, ENTER T

FOR NEW TEST DATA, ENTER '2'

TO QUIT, ENTER 3?"

You may take any of those three
actions by entering the indicated number.
Entering a T avoids the long delay to cre-
ate a new string array

Many of you have more than 16K
memory in your computers. You may
poke the machine language program into
the top of your memory by changing the
BASIC program line 190 to add 16384 (for
32K) or 32768 (for 48K) to both numbers
in the line. Since this produces addresses
above 32767, you will have to modify
each number by the formula:
- 1*(65536 - desired address).

Don't forget to change the MEMORY SIZE
accordingly. You also have to change the
calling address in line 270 by replacing the
126' with 190 (for 32K) or with 254 (for
48K). Next, fix the machine language pro-
gram absolute address data in lines
50000 and beyond by replacing '127'
with 191 (for 32K) or with 255 (for 48K)
everywhere but the first occurrence of
'127.' Finally fix the check in line 240 by
adding the amount you added in the data
substitutions. You are now able to size
bigger string arrays in lines 290, 300, 350,
and 360.

When adapting this technique to
other programs, be sure that you define Z
as an integer (after your last CLEAR com-
mand). Also, don't insert any other steps
in between your equivalent of lines 1 100
through 1 160. The machine language
program depends on this to find the data
being passed to it by the USR command.
Finally, if any of the VARPTR's in lines
1 140 or 1 150 are negative, they must be
converted by adding 65536 to each neg-

( Continued on page 16)

5on — Listinj

g L (from page 14)

7F96 3AFA7F

01340

LD

A,(DIMENS>

7F99 47

01350

LD

BtA

7F9A C5

01360

PUSH

BC

01370

5BYPASS FOR 1ST SWAP

7F3B 180D

01380

JR

SWAP1

01390 5 MOVE TO

NEXT

COLUMN

7F9D C5

01400 SWAP

PUSH

BC

7F9E ED4BFE7F

01410

LD

BCt(COLDEL)

7FA2 IB

01420

DEC

DE

7FA3 IB

01430

DEC

DE

7FA4 2B

01440

DEC

HL

7FA5 2B

01450

DEC

HL

7FAB 09

01480

ADD

HL ,BC

7FA7 EB

01470

EX

DE*HL

7FA8 09

01480

ADD

HL*BC

7FA9 EB

01490

EX

DE*HL

01500 5START M

ARPTR

SWAP

7FAA 4E

01510 SWAP1

LD

C,(HL)

7FAB EB

01520

EX

DE>HL

7FAC 7E

01530

LD

A»(HL)

7FAD 71

01540

LD

(HL) fC

7FAE EB

01550

EX

DE *HL

7FAF 77

015B0

LD

(HL) »A

7FB0 23

01570

INC

HL

7FB1 13

01580

INC

DE

01590

S2ND

BYTE SWAP

7FB2 4E

01600

LD

C>(HL)

7FB3 EB

01610

EX

DE>HL

7FB4 7E

01620

LD

A »(HL)

7FB5 71

01630

LD

(HL) *C

7FBB EB

01640

EX

DE,HL

7FB7 77

01650

LD

(HL) *A

7FB8 23

01660

INC

HL

7FB9 13

01670

INC

DE

01680

53RD

BYTE SWAP

7FBA 4E

01690

LD

C,(HL)

7FBB EB

01700

EX

DE *HL

7FBC 7E

01710

LD

A*(HL)

7FBD 71

01720

LD

(HL) »C

7FBE EB

01730

EX

DE,HL

7FBF 77

01740

LD

(HL) .A

01750

5GET

COLUMN CTR

7FC0 CI

01760

POP

BC

01770

5 DO i

MEXT COLUMN

7FC1 10DA

01780

DJNZ

SWAP

7FC3 2AFS7F

01790

LD

HL> (ST0RDE)

7FCS EB

01800

EX

DE*HL

7FC7 2AEE7F

01810

LD

HLt(STORTl)

7FCA AF

01820

X0R

A

7FCB ED52

01830

SBC

HL *DE

7FCD 22EE7F

01840

LD

(ST0RT1 ) »HL

7FD0 D2377F

01850

JP

NC , REPEAT

7FD3 1802

01860

JR

EXIT

7FD5 Dl

01870 FINIS

POP

DE

7FDS El

01880

POP

HL

7FD7 2AF07F

01890 EXIT

LD

HL*(ST0RT2)

7FDA 110100

01900

LD

DE»i

7FDD AF

01910

X0R

A

7FDE 19

01920

ADD

HL >DE

7FDF 22F07F

01930

LD

(ST0RT2) jHL

7FE2 ED5BF27F

01940

LD

DE»(ST0RT3)

7FEG ED52

01950

SBC

HL>DE

7FE8 DA317F

01960

JP

C*AGAIN

7FEB C30F7F

01970

JP

CYCLE

0002

01980 ST0RT1

DEFS

(Continued on page 16)

15

Radio /hack The biggest name in little computers®

Out-of-Sorts

(from page 15)

atrve VARPTR (ED. We added line 1130
which handles negative VARPTR for line
1140, the most likely line to need correct-
ing.) This may be done with an IF . . .
THEN . . . statement in the same line. You
need not modify lines 1 1 10 or 1 160.

Now, let's get to work finishing all
those programs which require a fast sort-
ing subroutine!

Editor's comments: We modified the pro-
gram slightly (reduced the array from 150
x 5 to 100 x 5) so that it will run in either
a 16K Level II Model I, or a 16K Model HI
BASIC Model III.

The only restriction on the array
dimensions is the limits of your memory.
You might wish to look at the Model II ver-
sion of the demonstration program. In
that version, we allow the response to the
INPUTs to control the dimensioning of the
array A$.

In general we left Mr. Terrell's work
as we received it. We did renumber the
lines to make entry a little easier. Next
month we hope to present a second arti-
cle from Mr. Terrell called "Get Your Date
For Free "

Model III Level I
Manual Error

The Model III Level I manual, page
66, gives you a sample program to use
with your line printer.

Level I does not support the TAB
function with LPRINT. Change lines 10, 30
and 80 to read:
10 LPRINT "TELEPHONE

LIST"
30 LPRINT" " *"NAME" t *

"TELEPHONE NUMBER"
80 LPRIIW" " *A*» ,B*

These changes will let you use this
program so you can "play" with your line
printer. Please ignore all references to the
TAB function used with LPRINT.

Sort— Listing 1

0002
0002
0002
0002
0002
0002
0002
0002
0000
00000 TOTAL ERRORS

Please note the addresses in parenthesis are for the Model II version of this program,
ORGedatHexF000.

X (from page 15)

01990

ST0RT2

DEFS

2

02000

ST0RT3

DEFS

2

02010

ST0RHL

DEFS

2

02020

ST0RDE

DEFS

2

02030

STORM

DEFS

2

02040

DIMENS

DEFS

*?

02050

PTRDEL

DEFS

*?

020G0

C0LDEL

DEFS

<?

02070

END

AGAIN

BYPASS

C0LDEL

DIMENS

EXIT

POP

REPEAT

ST0RDE

ST0RN

ST0RT2

ST0R0

SNA PI

PARTIS

7F31
7F1C
7FFE
7FFA
7FD7
7F8A
7F37
7FFG
7F09
7FF0
7FF8
7FAA
(F12F)

(F052)
(F03D)
(F11F)
(F11B)
(F0F8)
(F0AB)
(F058)
(F117)
(F02A)
(Fill)
(F119)
(F0CB)
START

BACK

CLEAR

CYCLE

ENTRY

FINIS

PTRDEL

SKIP

ST0RHL

ST0RT1

ST0RT3

SWAP

(F121)

7F7C
7FS9
7F0F
7EDF
7FD5
7FFC
7F8G
7FF4
7FEE
7FF2
7F9D

(F09D)
(F08A)
(F030)
(F000)
(F0FG)
(F11D)
(F0A7)
(F115)
(F10F)
(F113)
(F0BE)

Machine Sort — Listing 2 Basic Program

100
110

120
130
140
150

1G0
170
180
130
200
210
220
230
240
250
2G0

270
280

290
300
310
320
330
340

350

3G0
370

380
390
400

*** 2D ARRAY SORT BASED ON ALLEN EMERT PROGRAM

FROM JULY 80 TRS-80 MICROCOMPUTER NEWSLETTER
MODIFIED BY WILLIAM TERRELL OCT 80
FOR ARRAYS OF THE FORM A$(I>J) ***

*** POKE MACHINE LANGUAGE PROGRAM INTO HIGH
MEMORY **#

### PROTECT MEMORY AT 32478 ***
POKE 1S553* 255
K =

FOR 1= 32479 TO 32749s READ J
K= K+ J
POKE It Jj NEXT I

*** CHECK MACHINE LANGUAGE PROGRAM ***

IF K <> 321G0 THEN PR I NT "DATA ERROR" s END
*** INITIALIZATION ***
*** SET UP CALLING ADDRESS OF MACHINE LANGUAGE

PROG ***

POKE 16526* 223: POKE 16527* 12G
*** SET UP DATA SPACE FOR ZR DATA SETS OF ZF

FIELDS ***

CLEAR 100005 DEFINT I-K* Zs ZR= 100s ZF= 5

DIM A$(ZR tZF) t Z(4) s Z=0

CLS

**# GENERATE AND DISPLAY TEST DATA FOR SORT
PROGRAM # # #

INPUT"NUMBER OF DATA SETS (100 MAX) YOU
WANT" 5 ZR

INPUT"H0M MANY FIELDS (5 MAX) IN EACH" 5 ZF
FOR 1= TO ZR-ls FOR J= TO ZF-ls A$(I»J)=
"": NEXTs NEXT
FOR 1= TO ZR-1
ZA= 5s PRINT Lf
FOR J = TO Z F - 1 (Continued on page 17)

16

Radio /haek The biggest name in little computers®

Pocket Program Sort— Listing 2

Measurement Conversion

Mr. A. R. Lewellen of Highland, ML
sent us this measurement conversion
program. Input a measure in feet and
decimal portions of feet, and the program
will convert to feet, inches and 16ths of
inches.

FT., IN., /16 CONVERSION

10:1

20

30

40

50

60

70

80

90

100

110

120:
130s
200s

2105

220:
230:
240:
250:
2B05
2705
280s
2905
300:

NPUT
iA
INT
A-
INT
C-
INT
F/
INT
F X =
K= IB
PRINT
D5 "
11 5 K
GOTO
END
G = F/
1= F/
IF G =

"ENTER DIMENSION

(A/ 12)
<B* 12)

(C)
D

( (E* 16)+ + 5)

Tf/ 2)

Y THEN 200

BS "
IN* 1 ' 5

FT*" 5

F5 "/

IF
K =
IF
K =
IF
K =
IF
K =
IF
K =
IF
K =
IF
K =
IF
F =
END

G =
8s
G =
8s
G =
8:
G =
8:
H =
4:
K =
4:
1 =

*? m
J =

0:

2: H= F/4s
8s J= F/1B

THEN 110

1 LET F= 1:
GOTO 110

3 LET F= 3s

GOTO 110

5 LET F= 5s

GOTO 110

7 LET F= 7:

GOTO 110

1 LET F= Is

GOTO 110

3 LET F= 3:

GOTO 110

1 LET F= Is

GOTO 110

1 LET D= D+ls

K= 18: GOTO 110

(from page 9)

Color

If you use these last 4 instructions in
the sequence listed here, you will have set
up the beginning of your program for
graphics or text. All that is left is the input
routines for the data and what you want
to do with that data.

As you can see, Extended Color
BASIC is a powerful language, but with
simple commands that allow you to use
it. Programming is relatively easy to learn
and do (especially using the Extended
Color BASIC manual provided with either
he computer or the kit). For those of you
who only need the instruction set, there is
also a quick reference card included with
the computer.

410
420
430

440
450
1000
1010

1020
1030
1040
1050

1060
1070
1080

1090
1100
1110
1120
1130

1140

1150
1160
1170
1180
1190
1200
1210
1220

1230

1240

1250

1260

1270

1280

1290

1300

1310

1320

1330

1340

1350

1360

50000

50010

50020

50030

50040

50050

50080

50070

50080
50090

50100

(from page 16)

FOR K=l TO RND(10)

A$U*J) = A$(I*J>+ CHR$(RND(26)+S4)

NEXT Ks PRINT TAB(ZA)S A$(I*J)Ss ZA =

NEXTJ

PRINT: NEXT I

ZA+ 12;

*** SORT ROUTINE ***

*** VARIABLES PASSED TO MACHINE LANGUAGE

PROGRAM ***
Z(0) = NUMBER OF DATA SETS
Z(l) = POINTER TO FIELD BEING SORTED
Z(2) = NUMBER OF FIELDS IN DATA
Z(3) = POINTER DELTA: SORTED FIELD TO ZERO
FIELD
2(4) = POINTER DELTA: FIELD TO FIELD

INPUT"SORT ON WHICH FIELD (ZERO IS 1ST) "5

INPLTT'PRESS 'ENTER' WHEN READY" 5 ZZ

Z(0)= ZR

ZU) = OARPTR(A$(0*ZC) )

Z(2)= ZF

IF Z(1)<0 AND OARPTR(A$(0 *0) ) >0 THEN

Z(3) =65536+ Z(i) - OARPTR ( A$ ( *0 ) ) s GOTO

1150

Z(3)= ABS(OARPTR(A$(0 *ZC) )- UARPTR ( A$ < *0

) ) )

Z(4)= MARPTR(A$(0*1) ) - OARPTR ( A$ ( *0 ) )

Z=USR(OARPTR(Z(0) ) )

*#* DISPLAY DATA *#*
GOSUB 1290

*** BRANCH TO NEXT ACTION ***

PRINT"FOR ANOTHER SORT ON SAME

DATA*
PRINT'
INPUT'
ON ZZ
END

ENTER '1'"

FOR NEW TEST DATA* ENTER '2'
TO QUIT* ENTER '3'" ? ZZ
GOTO 1080* 350* 1260

###

DISPLAY ROUTINE ***
FOR 1= TO ZR-1
K= 5s PRINT I 5
FOR J= TO ZF-1
PRINT TAB(K) 5 A$(I *
K= K+ 12
NEXT Js PRINT
■NEXT Is RETURN

J)

' * DATA
DATA 205 *
DATA 35*
DATA 35*
DATA 237 *
DATA 254*
DATA 246*
DATA 251 *
10

DATA 127*
DATA 240*

DATA 127*
235

TO POKE MACHINE LANGUAGE PROGRAM *
127* 10* 94* 35* 88* 237* 83* 10*
94* 35* 86* 237* 83* 248* 127* 35*
86* 237* 83* 250* 127* 35* 94* 35*
83* 252* 127* 35* 94* 35* 86* 237
127* 33* 0* 0* 34* 246* 127* 237*
127* 203* 59* 175* 203* 58* 48

* &

127

94

86

* 83
91

* 203
42*

237*
127*

82*
42*

34*
240

?42*
127 *

127* 33* 0* 0* 34
34* 238* 127* 42

237* 91* 246* 127* 25* 34* 244* 127:

(Continued on page 18)

17

Radio /hack The biggest name In little computers®

Peripherals

{from page 8)

I'm predicting this printer will be a
real winner! It is an ideal mate for the low
cost Color Computer. Its features and per-
formance make it an excellent choice for
many users of Model I and III machines
as well. Included in this article is a sample
of the graphic capabilities of Line Printer
VII. This unit should be arriving in quantity
at the warehouse in late March. Don't for-
get to order the proper cable. (Model I, III
— 26-1401 $39.95; Color — 26-3020
$4.95; Modelll— 26-4401 $39.95)

NOTES THAT FLOAT TO THE
TOP OF MY DESK

Line Printers VI (264.166) and VII
(26-1167) will be certified Class B by the
FCC, making them suitable for use with
Model III and the Color Computer in
home environments. (They produce less

Model I/III Printer
Routine

Here is a letter from GaryJ. Himler of
Granada Hills, CA:

"Thanks for publishing the hints,
routines, and short programs in the
NEWS. The Paging Routine by Richard
Halloran in the December issue is most
helpful. I have made some changes to
make it easier to use (at least I think so)
and have included the revised listing for
your readers, if you would like to publish
it.

"The following advantages are
gained:

"If the last line of the program listing
is "END" then line 90 will cause the LLIST-
ing to be terminated and the printer to go
to Top-of Form. It is no longer necessary
to know the number of lines in the pro-
gram, or to enter them in line 30 of Mr.
Halloran s program.

"Line 50 numbers each page of the
program in the upper right hand comer.

"If you save the program you wish to
list as "PROGRAM",A then it is not neces-
sary to change the name of the file to be
opened in line 20 for each program to be
LLISTed.

Here is the procedure I recommend:

Keep the LLIST program on disk.
Save the program to be listed as
"PROGRAM",A

Then enter RUN"LLIST"

"It is important that the number of
characters in a program line not exceed
the number of characters the printer can
print per line (80 for Line Printer II), oth-
erwise the pagination will get skewed."

18

TV interference than some of our other
printers.) To operate Model III to class B
standards it will be necessary to make
sure that your printer cable is shielded.
The shielded version of the cable (26-
1401 A) will become the new standard.
Jhey will be available sometime this
month. It's a lot more expensive cable but
will be supplied at no increase in price.
The use of the shielded version will
actually be necessary only in some
installations.

Some users have experienced prob-
lems with the ribbon used in LP III (and
now the LP V). Our studies have shown
that some of the troubles were caused by
over-use of the ribbon. Don't forget, with
a 2,000,000 character ribbon life, the LP
III will use up a ribbon in a little over 5
hours of printing and LP V in a little over 4
hours. Don't over-use that ribbon. The

new low price (26-1414 — $13.95)
should help that problem. AdditionaHy, all
LP V's will come with a head cleaning kit
designed to insure proper operation. Cur-
rent owners can obtain one through your
local Radio Shack store. Ask your man-
ager to order 700-3010. It will be supplied
at a suggested charge of $ 1.50.

Be sure to read the article in the April
issue which will cover the saga of LPC If
you are a user of our business packages
you may have run afoul of the great TOP
OF FORM mystery. Let's hope we can lay
it to rest.

Important — last month we told you
that the new Modem I (26-1172) worked
at both 300 and 600 baud. A last minute
change has made the Modem I work at
300 baud ONLY.

Thanks for reading this month. Look
for more news next month. Remember
—You read it here first!

10
20
30
40
50
S0
70
80

90

100

110

120

130

140

150

LLIST USED TO PRINT PAGINATED LISTING

70

160

170
180
130
999S

CLEAR 500

ON ERROR GOTO 150

CLSs PRINT@320 , "LOADING

OPENM" * 1 * "PROGRAM"

POKE 18425* 1

PN = PN+ Is LPRINT STRING$(

LPRINT" " : LPRINT" "

IF PEEK(1B425)= 50 THEN LPRINT

LINE INPUT #i *R$

LPRINT R$

IF RIGHT$(R$*3)=

LPRINT CHR$(12)

GOTO 9999

CLS: PRINT@192*

SAME THE PROGRAM

PRINT:

PRINT:

'PROGRAM' INTO MEMORY'

) "PAGE

PH\

CHR$(12) s GOTO 80

"END" CLOSE ELSE 90

LISTING *

TO PRINT A PAGINATED

TO BE LISTED"
PRINT"USING THE COMMAND SAUE 'PROGRAM' *A"
PRINT"THEN RUN 'LLIST'"

PRINT: PRINT:
GOTO 9999
END

PRINT

Sort— Listing 2

(from page 17)

50110
50120
50130
50140
50150
501S0
50170
50180

50190
50200
50210

50220
50230

50240

50250
502S0
50270

DATA

DATA

DATA

DATA

DATA

DATA

DATA

DATA

235

DATA

DATA

DATA

35

DATA

DATA

24S

DATA

238

DATA

DATA

DATA

15*

33* 0* 0* 25* 25* 25* 229* 237* 91* 238
127* 33* 0* 0* 25* 25* 25* 237* 75* 248
127* 9* 235* 225* 9* 229* 213* 14* 0* 12S
71* 2S * 184* 48* 3* 14* 1* 71* 175* 17G
40* 25* 197* 19* 35* 78* 35* 70* 197* 225
235* 78* 35* 70* 197* 225* 193* 26* 150* 5B
10* 32* 83* 19* 35* 18* 248* 203* 85* 32
75* 237* 75* 252* 127* 175* 225* 237* 88*

225* 237* 88* 58* 250* 127* 71* 197* 24* 13
197* 237* 75* 254* 127* 27* 27* 43* 43* 9
235* 9* 235* 78* 235* 128* 113* 235* 119*

19* 78* 235* 128* 113* 235* 119* 35* 19* 78
235* 128* 113* 235* 119* 193* IB* 218* 42*

127* 235* 42* 238* 127* 175* 237* 82* 34*

127
127
91 *
127

* 210* 55* 127* 24* 2* 209* 225* 42* 240

* 17* 1 * 0* 175* 25* 34* 240* 127* 237
242* 127* 237* 82* 218* 49* 127* 195*

Radio /haeH — The biggest name in little computer^

(TM)

Model II Version Listing l .
Sort

The following information will allow
Model II users to use this month's
machine language sort routine. Please
read the article under Model I/III for infor-
mation about the sort itself. Here we will
present the information you need to con-
vert the machine language routine to
Model II, as well as present you with a
BASIC program which will demonstrate
the sort.

If you wish to assemble the sort pro-
cedure, make the following changes to
the assembly listing shown in the Model
I/III section:

1. Change the origin (ORG) from
7EDFH to FOOOH in line 1 10. If you wish
to assemble relocatable code, (using our
26-4702 Editor/Assembler), leave out the
ORG statement and use this address (or
your own) with the linking loader.

2. Delete the CALL 0A7FH statement
in line 130. In its place put three (3) NOP
statements.

3. At the end of the listing, delete the
END statement and ADD the code shown
in listing 1.

4. Assemble and debug the code.
For the sample BASIC program, you
should create a disk file with the filename
"SORT/CIM"

If you want to simply enter the code
into memory, and are not concerned with
relocating it from FOOOH, Listing 2 gives
the Hex values to enter using DEBUG. For
details on using DEBUG, see your
TRSDOS manual. The starting address is
FOOOH.

After you have finished entering the
Hex values using DEBUG, exit DEBUG
using the O option. DUMP the code to
disk using the command line shown in
listing 3.

Now enter and save the BASIC pro-
gram shown in listing 4. This is the sam-
ple program which demonstrates the
method of using the sort routine.

When you load BASIC, set memory
using BASIC -MsB1439. In your pro-
grams, the lines equivalent to 260 - 320
should not be modified, nor should any-
thing be added to them.

Have fun, and happy sorting! Our
thanks again to Allen Emert who provided
the original machine sort in our July 1980
issue, and to William Terrell who modified
that program to produce this new version.
We would also like to acknowledge Tom
Mornini of Fair Oaks, CA who suggested
we publish the assembly listing for Model
II, and whose disassembled listing helped
us in providing the above information.

Add this code to the end of the assembly language version of the sort routine:

F121

2100F0

02070

START

LD

HL»ENTRY

F124

E5

02080

PUSH

HL

F125

2A0328

02030

LD

HL >(2803H)

F128

E9

02100

JP

(HL)

F129

FE4F

02110

CP

4FH

F12B

2802

02120

JR

Z*PART19

F12D

CBC8

02130

SET

01H,B

F12F

DD7E04

02140

PART19

LD

A , (IX+04H)

F121

02150

END

START

Refer to your Editor/Assembler Users Guide for particular techniques and punctua-
tion requirements.

Listing 2.

Here is a

i Hex listing of the program if you

are using DEBUG to enter the machine

code. Note that the first four digits

tare'

the Hex beginning address for that line of entries:

F000

00

00

00

5E

23

5B

ED

53

2B

F0

23

5E

23

5B

ED 53

F010

19

Fl

23

5E

23

5G

ED

53

IB

Fl

23

5E

23

5G

ED 53

F020

ID

Fl

23

5E

23

56

ED

53

IF

Fl

21

00

00

99

17 Fl

F030

ED

5B

17

Fl

CB

3B

AF

CB

3A

30

02

CB

FB

ED

53 17

F040

Fl

7A

B3

C8

2A

2B

F0

ED

52

13

Fl

21

00

00 22

F050

11

Fl

2A

11

Fl

rjrj

0F

Fl

2A

0F

Fl

ED

5B

17

Fl 19

F0B0

22

15

Fl

EB

21

00

00

19

19

19

E5

ED

5B

0F

Fl 21

F070

00

00

19

19

19

ED

4B

19

Fl

09

EB

El

09

E5

D5 0E

F080

00

7E

47

1A

B8

30

03

0E

01

47

AF

B0

28

19

C5 13

F090

23

4E

23

4G

C5

El

EB

4E

23

4S

C5

El

CI

1A

96 38

F0A0

0A

20

53

13

23

10

FS

CB

41

20

4B

ED

4B

ID

Fl AF

F0B0

El

ED

42

EB

El

ED

42

3A

IB

Fl

47

C5

18

0D

C5 ED

F0C0

4B

IF

Fl

IB

IB

2B

2B

09

EB

09

EB

4E

EB

7E

71 EB

F0D0

77

23

13

4E

EB

7E

71

EB

77

23

13

4E

EB

7E

71 EB

F0E0

77

CI

10

DA

2A

17

Fl

EB

2A

0F

Fl

AF

ED

52

22 0F

F0F0

Fl

D2

58

F0

18

02

Dl

El

2A

11

Fi

11

01

00

AF 19

F100

22

11

Fl

ED

5B

13

Fl

ED

52

DA

52

F0

C3-

30

F0 FF

F110

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF FF

F120

FF

21

00

F0

E5

2A

03

28

E9

FE

4F

28

02

CB

C8 DD

F130

7E

04

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF

FF FF

Listing 3.

Use this command line to DUMP a copy of the machine code to disk with the file
name"SORT/CIM":
DUMP S0RT/CIM START=F000 > END=F140, TRA=F121* R0RT=R

Listing 4.

10 CLS

20 T$ = ,,,1 s Tl$=""

30 SYSTEM "LOAD S0RT/CIM"

40 CLEAR 23000, 61439

50 DEFUSR= &HF121

60 DEFINT A-Z

70 INPUT"IMUMBER OF DATA SETS" 5 ZR

80 INPUT"NUMBER OF FIELDS IN EACH SET" 5 ZF

90 DIM A*(ZR*ZF) » Z(4)

100 Z =

110 FOR 1=0 TO ZR-ls FOR J=0 TO ZF-1

120 A*(I »J)="": NEXT J, I

130 FOR 1=0 TO ZR-1

140 ZA = 5: PRINT I 5

150 FOR J=0 TO ZF-1

(Continued on page 20)

19

Radio /hack

MICROCOMPUTER NEWS

P.O. BOX 2910

FORT WORTH, TX 76101

BULK RATE

U.S. POSTAGE

PAID

Radio Shack
A Div. of Tandy Corp.

ADDRESS CHANGE

□ Remove from List

□ Change as shown

Please detach address
label and mail to
address shown above.

IF UNDELIVERABLE DO NOT RETURN

Model II Sort Listings

(from page 19)

1G0
170
180
190
200
210
220
230
240
250
2G0
270
280
290

300
310
320
330
340
350
3G0
370
380
390
400
410
420
430
440
450

480
470
480
490

FOR K=l TO RND(iB)

A$(I,J)= A$(I*J)+ CHR$(RND(2G)+ 84)
N E v T K
PRINT TAB(ZA) ; A$<I #J) 5
ZA = ZA+ 12: IF ZA>70 THEN PRINT: ZA=5
NEXT J
PRINT: NEXT I
IN PUT "SORT ON WHICH FIELD (ZERO IS 1ST)"; ZC
INPUT"PRESS ENTER WHEN READY"! ZZ
Tl$= TIME*
Z<0>* ZR
Z(l)= MARPTR(A$(0»ZC) )

2 ( ^ ) IS ~?p

IF Z(i)<0 AND UARPTR(A$(0,0))>0 THEN Z(3)= 85538+

Z(1)-OARPTR(A$(0,0) > : GOTO 310

Z(3)= ABS<VARPTR<A$(0fZC))-VARPTR<A*{0*0) ) )

Z(4) = OARPTR(A$(0,1) )-VARPTR(A*(0*0) )

Z= USR0(OARPTR(Z(0) ) )

T$= TIME$

FOR 1=0 TO ZR-1

PRINT I 5

K=5

FOR J=0 TO ZF-1

PRINT TAB(K) 5 A*(I »J) 5

K=K+12
NEXT J
PRINT
NEXT I
PRINT
PRINT
PRINT 1

PRINT'

IF K>70 THEN K=5:PRINT

T$*
'FOR

Tl$
ANOTHER

SORT ON THE SAME DATA * ENTER

•FOR

A NEW DATA SET* ENTER '2
INPUT"TO QUIT, ENTER '3"'5ZZ
ON ZZ GOTO 230 t 40 * 490
END

COMPUTER SERVICES ADDRESS
AND PHONE NUMBERS

8 AM to 7 PM Central Time

Computer Services

900 Two Tandy Center

Fort Worth, Texas 76102

1-800-433-1679 (WATS Except Texas)

1-800-772-5914 (WATS Inside Texas)

1-817-390-3583 (Switchboard)

TRS-80 Micrcomputer News: © 1981
Tandy Corporation, Fort Worth, Texas
76102 U.S.A. AH Rights Reserved

Reproduction or use, without
express written permission from Tandy
Corporation of any portion of this News-
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